Concentrated KH buffer supplement for all marine fish and reef aquaria. Alkalin8.3 helps increase pH stability in an aquarium by raising alkalinity. Highly-effective, it provides a strong source of carbonates, the molecule that makes up the majority by weight of aragonite, the mineral secreted by reefbuilding organisms as skeletal material. Continued addition raises pH until 8.3 is reached, at which point the pH remains unchanged and the alkalinity alone increases. Over 50% stronger than most competing products. Formulated by a marine scientist.